Bag top closures for consumer size bags



Aug. 31, 1965 H. K. FOX 3,203,622

BAG TOP CLOSURES FOR CONSUMER SIZE BAGS Filed Nov. 6, 1963 2Sheets-Sheet l INVENTOR. Murcia K Fox X/ KQM Z Q'Zwd Z/M lrramvers Aug.31, 1965 H. K. FOX 3,203,622

BAG TOP CLOSURES FOR CONSUMER SIZE BAGS Filed Nov. 6, 1963 2Sheets-Sheet 2 INVENTOR. A meup A1 Fax FIE". 5 Z/WW,Z/W

United States Patent 3,203,622 BAG TOP CLOSURES FOR CONSUMER SIZE BAGSHarold K. Fox, Minneapolis, Minn., assignor to Bemis Bro. Bag Company,Minneapolis, Minn., a corporation of Missouri Filed Nov. 6, 1963, Ser.No. 321,922 7Claims. ((1229-62) This invention is directed to providinga bag top closure of a construction that will prevent a finely dividedproduct from sifting through the folds adjacent the end flaps of theclosure. More particularly this invention is directed to providing asharp and fiat fold in overlapping portions of a bag top closure toprevent product sifting therethrough.

Flour, sugar and similar other products are frequently sold in consumersize bags in five and ten pound quantities having a Deltaseal bag topclosure, Deltaseal being a registered trademark of the assignee of thisapplication, and of a construction generally disclosed in U.S. Patents1,868,686 and 1,937,506. Such closures. which are generally made withautomatic equipment, consist of two sets of folds with adhesive appliedbetween the folds. Problems have been encountered with the second set offolds due to the two thicknesses of paper of the sidefiaps that foldover together. That is, the inner sheet will buckle or crumple up (ifboth sheets are the same length) because of the effective smaller radiusof the inner sheet. Therefore, a sharp fiat fold cannot be obtained.However, a fold must be sharp and flat to preclude a finely dividedproduct from sifting through at the fold. That is, usually in using theprocesses of the prior art, a small channel remains adjacent the secondset of folds and as a result sifting occurs. This invention is directedto overcoming the aforementioned problem.

One of the objects of this invention is to provide a new and novel bagtop closure made up of two sets of folds wherein the folds will be sharpand flat to prevent product sifting therethrough. A further object ofthis invention is to provide in a bag top closure of the general typeillustrated in FIGURES 22 and 6 respectively of U.S. Patents 1,868,686and 1,937,506 a new and novel seal in the area of the fold lines toprevent sifting of product therethrough. Still another object of thisinvention is to provide a plurality of slits in the bag top at the timeof bag manufacture such that the slits subsequently will be adjacent thefold lines of the side wall flaps and permit adhesive bleeding throughthe slits to form a positive seal in this area.

Other and further objects of this invention are those inherent in theinvention herein illustrated, described and claimed, and will beapparent as the description proceeds.

To the accomplishment of the foregoing and related ends, the inventionthen comprises the features hereinafter fully described and particularlypointed out in claims, the description setting forth in detail certainillustrative embodiments of the invention, these being indicative,however, of but a few of the various ways in which the principles of theinvention may be employed.

The invention is illustrated with reference to the drawings in whichcorresponding numbers refer to the same parts and in which:

FIGURE 1 is a vertical View of an empty bag in a flat folded conditionthat has been slitted in accordance with this invention;

FIGURE 2 is an enlarged fragmentary perspective view of the top portionof the bag of FIGURE 1 after it has been filled and adhesive applied tothe inner surface of one and panel and adjacent portions of the sidepanels.

3,203,622 Patented Aug. 31, 1965 FIGURE 3 is a view similar to FIGURE 2other than the one end panel has been folded down;

FIGURE 4 is a fragmentary perspective view of filled bag after thesecond step of the folding operation has been completed;

FIGURE 5 is a plan view of the filled bag after adhesive has beenapplied to the flaps and the flaps have been moved upwardly intermediatethe position of FIG- URE 2 and a completely folded and sealed position;

FIGURE 6 is an enlarged fragmentary vertical cross sectional viewgenerally taken along the line and in the direction of the arrows 66 ofFIGURE 5, the FIGURE 5 position of the flaps being illustrated in solidlines and the dotted line position illustrating the flaps in the FIG-URE 4 position;

FIGURE 7 is a further enlarged fragmentary plan view of a partiallyfolded flap, said view being generally taken along the line and in thedirection of the arrows 7-7 of FIGURE 6, other than no adhesive isshown, to illustrate the spreading of the tabs at the fold line of theflap;

FIGURE 8 is an enlarged vertical cross sectional view illustrating theeffective smaller radius of the inner sheet of a flap relative to theouter sheet, said view being generally taken along the line and in thedirection of the arrows 88 of FIGURE 4 other than the flap has nearlybeen folded to a flap sealed position;

FIGURE 9 is an enlarged view of one corner portion of FIGURE 2; and

FIGURE 10 is a plan view of a filled bag with the top thereof folded andsealed in accordance with this invention.

The bag 10 shown in FIGURE 1 is of the type commonly known as a flat bagother than each of the body walls adjacent the top edges (adjacent thebag mouth) has been provided with a plurality of slits or cuts at thetime of the bag manufacture. The bag 10 has a thumb notch 11 and when inthe fiat condition of FIGURE 1 has its body walls folded flatwiserelative to one another for convenience in storage and packaging, thetwo body walls being joined at contiguous edges in a manner to leave onopen bag mouth.

The aforementioned cuts are made at the top of the bag, both walls, moreclosely adjacent to one joined edge of the flat bag than the other asillustrated in FIGURE 1 and extend generally parallel to the edges ofthe flat folded bag. Thus if the bag is provided with six cuts asillustrated in FIGURE 1, the five small tabs 12 are provided. These tabsare formed in the bag body walls such that when the bag has been opened,filled and shaped to be of a generally rectangular configuration inhorizontal plane (see FIGURE 2), one group of tabs will be located inone upper corner portion of the adjacent portions of each of one endwall 15 and side wall 14 and the other group of tabs will be located inthe upper adjacent corner portion of each of the same end wall and theopposite side wall. That is, the tabs are formed such that each groupwill include tabs on either side of the respective fold line FF for thesecond set of folding operations as will be set forth hereinafter (seeFIG- URE 4).

After the bag has been provided with the tabs at the above describedlocations, it is filled with product (with or without interveningstorage and/ or shipment) and then at least the upper portion of thefilled bag is shaped to be of generally rectangular configuration asillustrated in FIGURE 2 wherein one group of tabs is located at eachcorner portion of the same end wall. Preferably at this time, anadhesive, for example, a strip of glue or paste 13 is applied to theinner surface of the top portion 15b of the end wall having slitstherein and continuing around on portions of the side walls such asillustrated in FIGURE 2. Although less desirable, glue could be appliedto the end wall opposite the one having the slits formed therein such asdescribed in US. Patent 1,868,686. Now the top portion (panel) 15a isfolded inwardly to be generally horizontal and overlay the material inthe bag by a dimension 11 (see FIGURE 4) and the top portion (panel) 15bof the slitted end wall is folded inwardly to have the portion thereofwith adhesive thereon completely overlay a portion of panel 15a.

With reference to the above paragraph, the adhesive 13 is applied to thebag to extend horizontally along the side wall having the thumb cut 11from adjacent the thumb cut to the end wall 15 having the tabs, alongsaid end wall and thence along the opposite side wall to a locationcorresponding to the thumb cut in the first mentioned side wall. Thestrip of adhesive is preferably located at a dimension k verticallyabove the lower extremities of the slits and is of a vertical dimensionL, the length of the slits being a dimension In (see FIGURE 9). Duringthe folding of the bag from the FIGURE 2 condition to that of FIGURE 4and somewhat during the subsequent folding of the fiaps 17 and 18, theglue or paste spreads to cover an area that corresponds to a position inFIGURE 9 at the bottom of the slits or slight below and likewise spreadsin the opposite direction. The folding of the bag top to the FIG- URE 4condition and appropriate application of pressure causes the adhesive 13to adhere to the portion of panel 15a and the portions of parts 14c ofthe flaps that it overlays.

As a result of the aforementioned two folding steps, the top portions ofthe side walls are folded to form laterally extending flaps 17 and 18,one flap extending outwardly of each side wall as illustrated in FIGURE4. Each flap of FIGURE 4, as illustrated in FIGURE 6, includes atriangular part 14a having a base integrally joined to the adjacent edgeof the generally vertical side wall 14, a quadrangular part 14b havingedges integrally joined to portion 15b and an edge of triangular part14a, a third part 140 which may be of a triangular or trapeziumconfiguration depending on the dimension h of portion 15a and a fourthpart 14d. Regardless of the resulting geometric shape of part 14c itwill have one edge integrally joined with portion 15a and a second edgeintegrally joined with triangular part 14a. Part 14d has one edgeintegrally joined to a third edge of 14b and another edge likewisejoined to a third edge of 140 and is located between overlappingportions of parts 140 and 14b and for the most part adjacent the apexportion of the flap. Thus for the width of the overlapping portions ofparts 14b and 140 and in a lateral direction from the adjacent apex A ofthe respective flap and the adjacent vertical side wall there are threethicknesses of material (14a, 14b, 14c), and adjacent the apex portion afourth thickness 14d; while for the remaining portion of the flap, thereare two thicknesses 14a, 14c and 14b, 14c respectively.

After the upper portion of the bag top has been folded to the FIGURE 4condition, then adhesive 21 is applied to the then upper surface of eachof the flaps to cover substantially the entire surface area thereof. Nowflap 18 is folded upwardly about the fold line FF from the dotted lineposition of FIGURE 6, through the solid line position thereof and thento the FIGURE position with appropriate application of pressure so thatadhesive 21 adheres to the adjacent surface of panels a, 15b. Likewiseflap 17 is folded to complete the sealed bag top closure illustrated inFIGURE 10.

For each flap for the entire length of each fold line there are at leasttwo thicknesses of material folded about said fold line and in the areaof overlap of parts 14b, 14c three thicknesses. As may be seen in partfrom FIGURE 8, which shows the flaps 17 in a nearly completely foldedcondition, to obtain a sharp flap fold about fold line FF theoverlapping portions of 14a, 14b have to fold about a single fold lineand each should have a single radius of curvature since theperpendicular distance from the fold line to apex A is the same whenthey are in the FIGURE 4 position. However due to the thickness ofmaterial, the overlapping portion of part 14b will effectively have ashorter radius of curvature than as they are folded through the FIGURE 8position. As a result, without the tabs of this invention, either 14band/or usually panel 15b of prior art bag disclosures crumples orbuckles to provide this effective shorter radius of curvative andthereby resulting in a small channel through the adhesive seals wheresifting can occur. Such a channel can result in automatic foldingoperations since the adhesive between overlapping portions of panels15a, 15b has not had a chance to set prior to the initiation of thefolding of the flaps.

In using the bag structure of this invention as the bag top is foldedfrom the FIGURE 4 position to the FIG- URE 5 position, the cutseliminate the rigidity of the bag in the area of the fold lines FF sothat the folding can be done with little or no resistance and the foldswill follow the line of least resistance in the area of the cuts. Thatis, during initiating the fold of a flap about the fold line FF, thefolding action tends to spread the adjacent tabs at the fold line as isillustrated in FIGURE 7 since the second thickiness 14c is adjacent thefirst thickness 14b and thereby exerts pressure laterally on the tabs asthe fold is being made. This in effect provides only a single thicknessof paper to be folded and as a result a sharp fold is obtained.

As the flaps 17 and 18 are folded from the FIGURE 4 position to theFIGURE 6 position, the glue which has been previously applied to adherethe portion of the top enclosure 15b that overlaps portion 15a to panel15a will bleed through the cuts of tabs 12 to make a better seal in thisarea. Accordingly a portion of 14c is adhered to the adjacent portion ofthe folded side wall portion 15b.

From the above it is believed apparent that in folding the bag topclosure of the aforementioned US. patents, frequently the glueintermediate the adjacent end wall portions 15a and 15b as designated inthe drawings of this application does not set sufliciently rapidly topreclude the portion of 15b that overlies portion 15a from pulling apartto form a channel adjacent each of the fold lines. This is in contrastto this invention wherein by providing the tabs, the tendency to formsuch channels is eliminated. Additionally due to the bleeding of theglue through the tabs, each flap part 140 in the area of the tabs isadhered to the underlying portion of panel 15a, and accordingly providesa positive seal in this area.

As an example of the invention but not a limitation thereon thefollowing dimensions are given. For consumer-size bags of five pound andten pound quantities, six cuts have been provided on each side wall,such that each tab thereby formed is '%a long and wide. However, it isto be understood that these cuts can be varied in size and number to fitany specific application in which this invention is to be used. Thedimension L is approximately Me", the dimension k /s" and the dimensionm Likewise the aforementioned dimensions are given as an example of theinvention but not as a limitation therein since they can be varied tofit any specific application in which this invention is to be used.

As many widely apparent different embodiments of this invention may bemade Without departing from the spirit and scope thereof, it is to beunderstood that I do not limit myself to the specific embodimentsherein.

What I claim is:

1. A bag in a fiat folded condition having adjacent body walls joined atcontiguous edges and having an open bag mouth, each of said walls havinga plurality of slits extending generally parallel to provide a pluralityof tabs at the portion of the respective wall adjacent the bag mouth,said tabs being located more closely adjacent one of said edges than theother and substantial spaced from each of said edges.

2. A bag body in open upright condition and shaped to have at least itsupper portion of a generally rectangular configuration to provide sidewalls and end walls, said side walls and end walls being joined atcontiguous edges, one end wall having two groups of a plurality ofvertical slits to form tabs at its upper portion, one group beinglocated adjacent each side wall.

3. A bag closure for an end portion of an upright bag body in opencondition that in at least the upper portion thereof is of a generallyrectangular configuration to provide side walls and end walls that arejoined at contiguous edges to form four corner portions comprising afirst panel joined to one end wall, a second panel joined to theopposite end wall and in part overlapping the first panel, a first flaphaving a first portion joined to one side wall, a second portion joinedto one edge of the first panel and a third portion joined to one edge ofthe second panel and at least in part overlaying said panels, a secondflap having a first portion joined to the other side wall, a secondportion joined to an opposite edge of the first panel, and a thirdportion joined to an opposite edge of the second panel and at least inpart overlaying said panels, said second portions and second panels eachhaving a group of slits forming tabs, the tabs in each portion and therespective second panel being adjacent one another, and adhesiveadhering the panel overlapping portions to one another, both the secondand third portions of each flap to one another and to the second panelin the area of the respective group of tabs, and non-tabbed areas of thesecond portions to areas of the second panel against which they abut.

4. The structure of claim 3 further characterized in that each of saidpanels is generally of a rectangular configuration, that each of saidflaps is generally of a triangular configuration and that each group oftabs is located adjacent the respective side Wall.

5. A bag closure for an end portion of a bag in a filled condition thatis in at least the upper portion of a generally rectangularconfiguration to provide side walls and end walls comprising a first endwall panel, a second end wall panel that at least partially overlaps thefirst end wall panel, said end wall panels being adhered to one anotheralong their overlapping portions, a first general triangular flapoverlaying a portion of said panels and adhered to at least one of saidpanels, said first flap including a first triangular part having oneedge integrally joined to one side wall and two quandrangular parts eachof which is integrally joined to a different panel and a second generaltriangular flap overlaying a portion of said panels and adhered to atleast one of said panels, said second tn'an- 5 gular flap including atriangular portion having an edge integrally joined to the opposite sidewall, the adjacent panel and quadrangular part being slitted to formtabs adjacent the juncture of the first triangular portion to the sidewall and both of said quadrangular parts and both of said panels beingadhered to one another at said tabs. 5 6. A bag body in an uprightcondition, having an open end, and shaped to have at least the portionadjacent said open end of a generally rectangular configuration toprovide side walls and end walls, said side walls and end walls beingjoined to form four corner portions adjacent the open end, two adjacentcorner portions each having a plurality of slits that intersect the openperipheral edge of the bag body to form generally vertical tabs.

7. A bag closure for an end portion of an upright bag body in an opencondition that in at least the upper portion thereof is of a generallyrectangular configuration to provide side walls and end walls that arejoined at contiguous edges to form four comer portions comprising afirst panel joined to one end wall; a second panel joined to theopposite end Wall and in part underlapping the first panel; a first flaphaving a first portion joined to one edge of the first side wall, asecond portion joined to one edge of the first panel and to one edge ofthe first flap first portion and having a free edge, and a third portionjoined to one edge of the second panel; a second flap having a firstportion joined to the other side wall, a second portion joined to anopposite edge of the first panel and to an edge of the second flap firstportion and having a free edge, and a third portion joined to anopposite edge of the second panel; each of said second portions havingsurface portions intermediate the respective first portion and at leastone of the panels; said second portions in the area of said surfaceportions each having a group of slits extending generally perpendicularto the respective free edge and located closely adjacent a wall; andadhesive adhering panel underlapping portions to one another, thesurface portions of said panels that abut against said flaps to saidflaps including the area of the second portion adjacent the tabs to boththe first panel and to the 40 respective first portion.

References Cited by the Examiner- UNITED STATES PATENTS 1,937,506 12/33Belcher s3-3s 2,093,979 9/37 Farmer 22962 2,126,203 8/38 Miskella 229622,176,996 10/39 Leonard et al. 53-38 2,271,647 2/42 Kindseth 229-62 X2,312,281 12/43 Claspill et al 229-57 X FRANKLIN T. GARRETT, PrimaryExaminer.

GEORGE O. RALSTON, Examiner.

7. A BAG CLOSURE FOR AN END PORTION OF AN UPRIGHT BAG BODY IN AN OPENCONDITION THAT IN AT LEAST THE UPPER PORTION THEREOF IS OF A GENERALLYRECTANGULAR CONFIGURATION TO PROVIDE SIDE WALLS AND END WALLS THAT AREJOINED AT CONTIGUOUS EDGES TO FORM FOUR CORNER PORTIONS COMPRISING AFIRST PANEL JOINED TO ONE END WALL; A SECOND PANEL JOINED TO THEOPPOSITE END WALL AND IN PART UNDERLAPPING THE FIRST PANEL; A FIRST FLAPHAVING A FIRST PORTION JOINED TO ONE EDGE OF THE FIRST SIDE WALL, ASECOND PORTION JOINED TO ONE EDGE OF THE FIRST PANEL AND TO ONE EDGE OFTHE FIRST FLAP FIRST PORTION AND HAVING A FREE EDGE, AND A THIRD PORTIONJOINED TO ONE EDGE OF THE SECOND PANEL; A SECONF FLAP HAVING A FIRSTPORTION JOINED TO THE OTHER SIDE WALL, A SECOND PORTION JOINED TO ANOPPOSITE EDGE OF THE FIRST PANEL AND TO AN EDGE OF THE SECOND FLAP FIRSTPORTION AND HAVING A FREE EDGE, AND A THIRD PORTION JOINED TO ANOPPOSITE EDGE OF THE SECOND PANEL; EACH OF SAID SECOND PORTIONS HAVINGSURFACE PORTIONS INTERMEDIATE THE RESPECTIVE FIRST PORTION AND AT LEASTONE OF THE PANELS; SAID SECOND PORTIONS IN THE AREA OF SAID SURFACEPORTIONS EACH HAVING A GROUP OF SLITS EXTENDING GENERALLY PERPENDICULARTO THE RESPECTIVE FREE EDGE AND LOCATED CLOSELY ADJACENT A WALL; ANDADHESIVE ADHERING PANEL UNDERLAPPING PORTIONS TO ONE ANOTHER, THESURFACE PORTIONS OF SAID PANELS THAT ABUT AGAINST SAID FLAPS TO SAIDFLAPS INCLUDING THE AREA OF THE SECOND PORTION ADJACENT THE TABS TO BOTHTHE FIRST PANEL AND TO THE RESPECTIVE FIRST PORTION.